OS 10.3 - Missing Utilities!

K, here's the deal. I'm helping my mom install divx player on her eMac. Problem is, the file extension is .pkg. I know to open this with Installer but when I double clicked on the icon, nothing would happen. I then searched for the Installer in the Utilities folder. Not only was that not there but a bunch of other ones weren't there. Somehow they were deleted. What do I do?